Semiconductor device

ABSTRACT

Provided is a semiconductor device applicable to both types of packages regardless of whether or not double bonding of a lead frame pad is allowed. The semiconductor device includes: an operational amplifier; a feedback resistor; a reference voltage generation circuit; an output transistor; a first pad which is connected to an output terminal of the output transistor, and is to be selectively connected to a lead frame pad by a bonding wire; a second pad to be selectively connected to the lead frame pad by a bonding wire; and a connection switching element provided between the first pad and the second pad. In a case in which the second pad is connected to the lead frame pad by the bonding wire, the connection switching element interrupts connection between the first pad and the second pad.

RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No.2021-010154, filed on Jan. 26, 2021, the entire content of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a semiconductor device.

2. Description of the Related Art

Hitherto, there has been devised a voltage regulator for suppressing anoutput voltage drop to be caused by a wiring resistance in a circuit ora bonding wire resistance, and supplying a highly accurate constantvoltage. FIG. 4 is a circuit diagram for illustrating a configurationexample of a related-art voltage regulator.

Bonding wires 4 a and 4 b are fixed to a lead frame pad 10 fromrespective pads 3 a and 3 b included in a semiconductor device 40. Inthis manner, a voltage at a feedback point can include a wiringresistance in a circuit and a bonding wire resistance.

Accordingly, the related-art voltage regulator illustrated in FIG. 4 iscapable of suppressing the output voltage drop to be caused by thewiring resistance in the circuit or the bonding wire resistance, andsupplying the highly accurate constant voltage (see, for example,Japanese Patent Application Laid-open No. Hei 07-161749).

In the related art, however, no consideration has been given toapplication to a package in which the bonding wires 4 a and 4 b cannotbe fixed to the lead frame pad 10. That is, it has been required toprepare two types of semiconductor devices depending on whether or notdouble bonding of the lead frame pad of the package is allowed.

SUMMARY OF THE INVENTION

The present invention has been made in view of the above-mentionedcircumstance, and has an object to provide a semiconductor deviceapplicable to both types of packages regardless of whether or not doublebonding of a lead frame pad is allowed.

According to at least one embodiment of the present invention, there isprovided a semiconductor device including: an operational amplifierconfigured to receive a reference voltage from a reference voltagegeneration circuit and a feedback voltage from a feedback resistor; anoutput transistor to be controlled by an output signal of theoperational amplifier; a first pad which is connected to an outputterminal of the output transistor, and is to be selectively connected toa lead frame pad by a bonding wire; a second pad to be selectivelyconnected to the lead frame pad by a bonding wire; a connectionswitching element provided between the first pad and the second pad; andthe feedback resistor connected to the second pad and the connectionswitching element, wherein, in a case in which the second pad isconnected to the lead frame pad by the bonding wire, the connectionswitching element interrupts connection between the first pad and thesecond pad.

Further, according to at least one embodiment of the present invention,there is provided a semiconductor device including: an operationalamplifier configured to receive a reference voltage from a referencevoltage generation circuit and a feedback voltage from a feedbackresistor; an output transistor to be controlled by an output signal ofthe operational amplifier; a first pad connected to an output terminalof the output transistor; and a second pad connected to the feedbackresistor, wherein, in a case in which any one of the first pad and thesecond pad is connected to a lead frame pad by a bonding wire, the firstpad and the second pad are connected to each other by a bonding wire.

According to the semiconductor device of the at least one embodiment ofthe present invention, it is possible to provide the semiconductordevice applicable to both types of packages regardless of whether or notdouble bonding of the lead frame pad is allowed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a circuit diagram for illustrating a semiconductor deviceaccording to a first embodiment of the present invention.

FIG. 2 is a circuit diagram for illustrating another example of thesemiconductor device according to the first embodiment.

FIG. 3 is a circuit diagram for illustrating a semiconductor deviceaccording to a second embodiment of the present invention.

FIG. 4 is a circuit diagram for illustrating a related-art semiconductordevice.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, embodiments of the present invention are described with referenceto the drawings.

First Embodiment

FIG. 1 is a circuit diagram for illustrating a semiconductor deviceaccording to a first embodiment of the present invention.

A semiconductor device 1 of FIG. 1 includes an operational amplifier 2,pads 3 a and 3 b, an output transistor 5, a feedback resistor 6, areference voltage generation circuit 7, and a connection switchingelement 8. The connection switching element 8 is formed of a fuse. Theoutput transistor 5 is formed of a PMOS transistor.

The operational amplifier 2 includes an inverting input terminal (−)connected to an output terminal of the reference voltage generationcircuit 7, a non-inverting input terminal (+) connected to an outputterminal of the feedback resistor 6, and an output terminal connected toa gate of the output transistor 5. The output transistor 5 includes asource connected to a power supply terminal, and a drain connected toone end of the connection switching element 8 and the pad 3 acorresponding to an output terminal of the semiconductor device. Anotherend of the connection switching element 8 is connected to the pad 3 band one end of the feedback resistor 6. Another end of the feedbackresistor 6 is connected to a ground terminal. Another end of thereference voltage generation circuit 7 is connected to the groundterminal.

Bonding of the semiconductor device of the first embodiment indicates acase of a package in which a lead frame pad 10 is not adapted to doublebonding. That is, the lead frame pad 10 is connected to the pad 3 a by abonding wire 4 a, but the lead frame pad 10 is not connected to the pad3 b.

The semiconductor device of the first embodiment is configured asfollows depending on the shape of the lead frame pad 10 of the package.

In the case of the package in which the lead frame pad 10 is not adaptedto double bonding, the pad 3 a is connected to the lead frame pad 10 bythe bonding wire 4 a without cutting the fuse being the connectionswitching element 8.

In a case of a package in which the lead frame pad 10 is adapted todouble bonding, the fuse being the connection switching element 8 iscut. Further, the pad 3 a is connected to the lead frame pad 10 by thebonding wire 4 a, and the pad 3 b is connected to the lead frame pad 10by a bonding wire 4 b (not shown).

The semiconductor device of the first embodiment is configured asdescribed above. In this manner, the semiconductor device of the firstembodiment is applicable to both types of packages regardless of whetheror not double bonding of the lead frame pad is allowed.

FIG. 2 is a circuit diagram for illustrating another example of thesemiconductor device of the first embodiment.

The semiconductor device of FIG. 2 includes a connection switchingelement 8 a formed of a PMOS transistor as the connection switchingelement, and a control circuit 9 configured to supply a control signalfor controlling the connection switching element 8 a. Other circuits aresimilar to those of the semiconductor device of FIG. 1 . Thus,description thereof is omitted.

The semiconductor device of FIG. 2 can be similarly applied by turningon and off the PMOS transistor of the connection switching element 8 athrough use of the control signal supplied from the control circuit 9,depending on the shape of the lead frame pad 10 of the package. In thiscase, the connection switching element 8 a is not limited to the PMOStransistor, and may be an NMOS transistor or an analog switch.

The control circuit 9 may be formed of, for example, a logic circuit ora test circuit, and may be configured to supply the control signal inresponse to an input signal from a test terminal or the like.

FIG. 3 is a circuit diagram for illustrating a semiconductor deviceaccording to a second embodiment of the present invention.

A semiconductor device 1 of FIG. 3 includes an operational amplifier 2,pads 3 b and 3 c, an output transistor 5, a feedback resistor 6, and areference voltage generation circuit 7. The pad 3 c is formed into asize adapted to double bonding.

The operational amplifier 2 includes an inverting input terminal (−)connected to an output terminal of the reference voltage generationcircuit 7, a non-inverting input terminal (+) connected to an outputterminal of the feedback resistor 6, and an output terminal connected toa gate of the output transistor 5. The output transistor 5 includes asource connected to a power supply terminal, and a drain connected tothe pad 3 c corresponding to an output terminal of the semiconductordevice. The pad 3 c is connected to the pad 3 b by a bonding wire 4 c.The pad 3 b is connected to one end of the feedback resistor 6. Anotherend of the feedback resistor 6 is connected to a ground terminal.Another end of the reference voltage generation circuit 7 is connectedto the ground terminal.

Bonding of the semiconductor device of the second embodiment indicates acase of a package in which a lead frame pad 10 is not adapted to doublebonding. That is, the lead frame pad 10 is connected to the pad 3 c by abonding wire 4 a, but the lead frame pad 10 is not connected to the pad3 b.

The semiconductor device of the second embodiment is configured asfollows depending on the shape of the lead frame pad 10 of the package.

In the case of the package in which the lead frame pad 10 is not adaptedto double bonding, the pad 3 b and the pad 3 c are connected to eachother by the bonding wire 4 c, and the pad 3 c is connected to the leadframe pad 10 by the bonding wire 4 a.

In a case of a package in which the lead frame pad 10 is adapted todouble bonding, the pad 3 b and the pad 3 c are not connected to eachother by the bonding wire 4 c. The pad 3 c is connected to the leadframe pad 10 by the bonding wire 4 a, and the pad 3 b is connected tothe lead frame pad 10 by a bonding wire 4 b (not shown).

The semiconductor device of the second embodiment is configured asdescribed above. In this manner, the semiconductor device of the secondembodiment is applicable to both types of packages regardless of whetheror not double bonding of the lead frame pad is allowed.

The embodiments of the present invention have been described above, butthe present invention is not limited to the above-mentioned embodiments.It should be understood that various modifications can be made theretowithout departing from the gist of the present invention.

For example, in FIG. 1 and FIG. 2 , the pad 3 b and the lead frame pad10 may be connected to each other by a bonding wire. Further, forexample, the pad 3 b of FIG. 3 may be configured similarly to the pad 3c, and may be connected to, in place of the pad 3 c, the lead frame pad10 by a bonding wire.

What is claimed is:
 1. A semiconductor device, comprising: anoperational amplifier configured to receive a reference voltage from areference voltage generation circuit and a feedback voltage from afeedback resistor; an output transistor to be controlled by an outputsignal of the operational amplifier; a first pad which is connected toan output terminal of the output transistor, and is to be selectivelyconnected to a lead frame pad by a first bonding wire; a second pad tobe selectively connected to the lead frame pad by a second bonding wire;a connection switching element provided between the first pad and thesecond pad; and the feedback resistor connected to the second pad andthe connection switching element, wherein, the connection switchingelement interrupts connection between the first pad and the second padin a case that the second pad is connected to the lead frame pad by thesecond bonding wire.
 2. The semiconductor device according to claim 1,wherein the connection switching element is a fuse.
 3. The semiconductordevice according to claim 1, wherein the connection switching element isa switching circuit.
 4. A semiconductor device, comprising: anoperational amplifier configured to receive a reference voltage from areference voltage generation circuit and a feedback voltage from afeedback resistor; an output transistor to be controlled by an outputsignal of the operational amplifier; a first pad connected to an outputterminal of the output transistor; and a second pad connected to thefeedback resistor, wherein, a connection between the first pad and thesecond pad is disconnected in a case that the first pad and the secondpad are connected to a lead frame pad.